Transfection is the process of introducing certain nucleic acids into a eukaryotic cell by means other than through a virus. Nucleic acids commonly used in transfection include DNA, RNA, and proteins, among other materials. Eukaryotic cells, like those found in human beings, contain the nucleus and other complex structures inside a membrane, unlike prokaryotic cells which do not. While a virus has the potential to transmit these foreign items through a cell's membrane and into the cell, transfection uses methods other than a virus for transmission. This method is a key technique used by scientists in genetic research to determine how the addition of a certain DNA or other foreign material will affect the cell.
Two main types of transfection exist: transient transfection and stable transfection. In transient transfection, the DNA is brought into the cell but the cell eliminates it before splitting into a new cell. Thus, the new DNA material does not carry over to the new cells and they are unaffected.
In stable transfections, the new DNA becomes part of the cell's original DNA by either adding on to it or replacing a piece of the old DNA. When the cell creates new copies of itself, the new DNA is passed on. It enters the nucleus and bonds with the old DNA to create a new DNA strand. This is a rare occurrence, as the cell typically eliminates the new material sometime after it enters but before the cell forms new cells. Despite this, scientists are constantly finding new ways to perform this process in experiments for the purpose of studying how the new DNA affects copies of the cells.
Similar processes known as transformation and transduction relate to transfection by transferring DNA or other matter into the cell. When a virus transfers new DNA into a cell, this is called transduction. Transformation does not involve a virus, but instead is the transfer of DNA into types of plant cells, bacteria, and eukaryotic cells found outside those of humans and animals. All deal with the same process, but the terms vary by the carrier — be it virus or non-virus — and the type of cell receiving the new DNA.
Gene research, experimentation, and therapy all rely on these processes to study the effects of DNA, RNA, and various proteins on the human cells. In the future, this process could help cure diseases, fix genetic mutations, and help improve the human body overall. Scientists continue to make great leaps forward in the quest for healthier people who live longer lives.